The invention provides a method for
cutting a
light emitting diode chip through deep
etching. The method comprises the following steps: firstly, forming a light emitting element comprising a plurality of light emitting units on the surface of a
semiconductor substrate; then fabricating a protecting layer with
etching windows formed at the connections between each of the light emitting units;
etching from each of the etching windows to form sliver channels; next, filling each of the sliver channels with insulation material and
thinning the
semiconductor substrate from back until exposing the insulation material; and finally making a back
coating, removing the insulation material in each of the sliver channel, and expanding the film to obtain independent light emitting units. According to the invention, by adopting the method of forming the sliver channels through deep etching, the
cut grooves are deep into the
sapphire substrate, thus avoiding
laser cutting processing step, avoiding the problem of light absorption caused by
laser ablation, and increasing light outgoing efficiency; and the deep etching depth is equivalent to the final thickness of the
chip, and separated
chip grains can be obtained by removing the filled SiO2, thus reducing sliver operation, avoiding broken sides and broken corners in the slivers, and increasing the yield.